Etymology of the words 'vedi' in ritual context

[Toke Lindegaard Knudsen]

Dear list members,

The Sanskrit word 'vedi' in ritual context (as found in for example
the zulbasUtras) means a raised area on which a sacrifice is
performed.  As the word seems to be derived from the root /vid 'to
know', how did it come to denote a sacrificial area?  Is there any
etymologi to explain this?

Thank you very much.

Sincerely,
Toke Lindegaard Knudsen